The present invention relates to a lubricant for a tire and wheel assembly to reduce friction between the inner wall of a tire and the rim or other parts of the vehicle wheel, with the lubricant containing, among other things, polyethylene glycol (polyglycol) and/or polyglycol ether.
United Kingdom Pat. No. 1,359,469, which is being incorporated into this disclosure by this reference thereto, discloses a number of materials that appear suitable for use as a lubricant; one of these materials is polyethylene glycol. The task of such a lubricant is to prevent damage or destruction of the tire due to slippage when the tire is operated for a long period of time in a deflated state. This is to be accomplished by reducing the friction between the inner wall of the tire and the rim or other parts of the vehicle wheel as they make contact when the tire is supported on the ground. Reduction of friction should also prevent an excessive amount of heat from being generated.
Various requirements are imposed for such lubricants for a tire and wheel assembly. For example, such lubricants should be able to maintain a high viscosity over as great a temperature range as possible. They cannot weigh much, so that they do not have too great of an effect upon the negative balance within the framework of an energy-optimized tire and wheel assembly. Furthermore, such lubricants cannot have too great of a tendency to flow, and must adhere to a sufficient degree to the rim or to the tire in order to assure a uniform distribution of the lubricant over the periphery of the tire or wheel even for long periods of time, and during the high contrifugal forces that are encountered during operation.
Unfortunately, none of the heretofore known lubricants has gained universal acceptance, because up to now none of the lubricants could simultaneously fulfill all of the requirements to a sufficient degree.
It is therefore an object of the present invention to provide an improved lubricant for tire and wheel assemblies.